Water-Resistant Products Using a Wax Emulsion

ABSTRACT

Embodiments of the present disclosure are directed to water-resistant products which contain a wax emulsion, or silicones, or siliconates, or fluorinated compounds, or stearates, or combinations thereof. In some embodiments, the compound can be used to provide enhanced moisture resistance to joints, or holes such as screw holes or nail holes, in a wallboard.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a divisional of U.S. application Ser. No.14/567,018 filed Dec. 11, 2014, which is a continuation-in-part of U.S.application Ser. No. 14/278,919, filed May 15, 2014 (now Abandoned),which claims priority from U.S. Provisional Application Ser. No.61/953,640, filed Mar. 14, 2014; U.S. Provisional Application No.61/946,396, filed Feb. 28, 2014; U.S. Provisional Application No.61/942,490, filed Feb. 20, 2014; and U.S. Provisional Application61/914,850, filed Dec. 11, 2013. The entire contents of theseapplications are hereby incorporated by reference herein.

TECHNICAL FIELD

Water-resistant products, such as joint compounds, using a wax emulsionare disclosed.

BACKGROUND

Wax emulsions have been used in composite wallboard (e.g., gypsumwallboard) for many years. For example, wax emulsions sold under thetrade name AQUALITE® by Henry Company, and several wax emulsionformulations are disclosed in the prior art, such as U.S. Pat. No.5,437,722.

Gypsum is employed in a gypsum panel or board product known as wallboardwhich is widely used as a structural building panel. Gypsum products maybe produced by mixing anhydrous calcium sulfate or calcium sulfatehemihydrate with water and allowing the mixture to hydrate or set ascalcium sulfate dihydrate, which is relatively hard. Gypsum wallboardmay comprise a panel-like core of set gypsum sandwiched between a pairof paper liners which form the exposed outer surfaces of the wallboard.Fiberglass liners have also been used. In many applications wallboard isexposed to water. A problem with set gypsum is that it absorbs water,and such absorption reduces the strength of the wallboard.

Further, in order to achieve a smooth, visually appealing surface, thejoints between boards, cracks, screw holes, and/or nail holes must beconcealed. Conventional wallboard joint compounds are commonly used tocover and finish gypsum wallboard joints, cornerbead, and screw or nailholes. Joint compounds can be spread over mesh or tape used to connectwallboards. It may also be used to patch and texture interior walls.

The intrusion of water through wall spaces, either through prolongeddirect contact or via high humidity, has a debilitating effect (mold andstructural damage) on standard wall systems. It is for this reason thatmoisture resistant wallboard, passing ASTM C473, was developed. Anintegral part of the wall system is the tape joint compound which, sofar, has no accepted standards for water resistance.

Some specially formulated gypsum wallboards (also called “Green” boards)contain a water repellent additive such as a wax emulsion to impart theadded functionality of water resistance to the board. While such “green”gypsum wallboards meet strict water repellency performance requirements(ASTM C473), there are no such requirements and indeed, no ready-mixjoint compound that offers commensurate water repellency. Consequently,the ready-mixed joint compound is a severe vulnerability in existingwall systems where protection against water damage is crucial. Theresult of water seepage through joint compound to the studs on the otherside of the wall ultimately has devastating structural and microbialimplications for the wall system, first by absorption of the seepedwater into the wood studs followed by their swelling and deformation(leading to expensive structural problems) and then, the creation of afertile ground for rapid mold growth. Conventional ready mixed jointcompound is therefore a weak link in the long term microbial resistanceand integrity of the wall system.

SUMMARY

The following presents a simplified summary of one or more aspects inorder to provide a basic understanding of such aspects. This summary isnot an extensive overview of all contemplated aspects, and is intendedto neither identify key or critical elements of all aspects nordelineate the scope of any or all aspects. Its sole purpose is topresent some concepts of one or more aspects in a simplified form as aprelude to the more detailed description that is presented later.

Disclosed herein are embodiments of a water-resistant joint compoundwhich can comprise water, preservative, and wax emulsion, or silicone,or siliconate, or fluorinated compound, or stearate, or combinationsthereof.

In some embodiments, the joint compound can comprise a wax emulsion andcan have a contact angle of about 90 to about 130 degrees, a pH below12, and a Cobb value of about 1.0 to about 200 grams per square meter.

In some embodiments, the joint compound can further comprise about 20 toabout 55 wt. % water, about 0.02 to about 1.0 wt. % preservatives, about10 to about 50 wt. % calcium carbonate, about 0.0 to about 10% mica,about 0.0 to about 10 wt. % attapulgite clay, about 0.0 to about 10 wt.% talc, about 0.0 to about 40 wt. % perlite, about 0.0 to about 10 wt. %polyethylene oxide, about 0.0 to about 10 wt. % polyether siloxane,about 0.1 to about 20 wt. % wax emulsion, about 0.5 to about 10 wt. %latex binder, and about 0.1 to about 8.0 wt. % cellulose etherthickener.

In some embodiments, the joint compound can further comprise a rheologymodifier, a binder, a thickener, and a filler. In some embodiments, thejoint compound can further comprise calcium carbonate, or cristobalite,or a micro-roughened filler, or gypsum, or mica, or clay, or thickener,or a latex binder, or talc, or perlite, or expanded perlite, orcombinations thereof. In some embodiments, the joint compound cancomprise a wax emulsion which can comprise water. polyvinyl alcohol,paraffin wax, or montan wax, or synthetic wax, or combinations thereof,a base, and a dispersant.

In some embodiments, the joint compound can comprise wax emulsion, thewax emulsion can comprise paraffin wax, or montan wax, or carnauba wax,or sunflower wax, or rice wax, or tallow wax, or a wax containingorganic acids and/or esters, or a emulsifier containing a mixture oforganic acids such as stearic acid and/or esters, or combinationsthereof. In some embodiments, the joint compound can comprise waxemulsion, the wax emulsion can comprise synthetic wax includingpolyethylene glycol or methoxypolyethylene glycol, or both polyethyleneglycol and methoxypolyethylene glycol. In some embodiments, the jointcompound can comprise synthetic wax at about 0.1% to about 8% of thejoint compound dry weight.

In some embodiments, the joint compound can comprise wax emulsionstabilized with polyvinyl alcohol. In some embodiments, the jointcompound can have a pH below 9. In some embodiments, the joint compoundcan have a contact angle of about 60 to about 130 degrees. In someembodiments, the joint compound can be generally hydrophobic and canhave a contact angle of about 110 to about 130 degrees. In someembodiments, the joint compound can have a Cobb value of about 1.0 toabout 200 grams per square meter. In some embodiments, the jointcompound can have a Cobb value of about 65 grams per square meter.

In some embodiments, the joint compound can comprise wax emulsion andsilicones, or siloxanes, or siliconates, or fluorinated compounds, orstearates, or combinations thereof. In some embodiments, the jointcompound can further comprise surface micro-roughened fillers.

Also disclosed herein is a method of making a water-resistant jointcompound which can comprise mixing a combination of water, preservative,and wax emulsion, or silicone, or siliconate, or a fluorinated compound,or stearate, or combinations thereof to form a water-resistant jointcompound.

In some embodiments, the joint compound can comprise a wax emulsion andcan have a contact angle of about 90 to about 130 degrees, a pH below 9,and a Cobb value of about 5.0 to about 200 grams per square meter.

In some embodiments, the joint compound can further comprise about 20 toabout 55 wt. % water, about 0.02 to about 1.0 wt. % preservatives, about10 to about 50 wt. % calcium carbonate, about 0.0 to about 10% mica,about 0.0 to about 10 wt. % attapulgite clay, about 0.0 to about 10 wt.% talc, about 0.0 to about 40 wt. % perlite, about 0.0 to about 10 wt. %polyethylene oxide, about 0.0 to about 10 wt. % polyether siloxane,about 0.1 to about 20 wt. % wax emulsion, about 0.5 to about 10 wt. %latex binder, and about 0.1 to about 8.0 wt. % cellulose etherthickener.

In some embodiments, the joint compound can further comprise a rheologymodifier, a binder, a thickener, and a filler. In some embodiments, thejoint compound can further comprise calcium carbonate, or cristobalite,or a micro-roughened filler, or gypsum, or mica, or clay, or thickener,or a latex binder, or talc, or perlite, or expanded perlite, orcombinations thereof. In some embodiments, the joint compound cancomprise wax emulsion stabilized with polyvinyl alcohol. In someembodiments, the joint compound can comprise wax emulsion comprisingsynthetic wax. In some embodiments, the joint compound can comprise waxemulsion, the wax emulsion can comprise synthetic wax includingpolyethylene glycol or methoxypolyethylene glycol, or both polyethyleneglycol and methoxypolyethylene glycol.

In some embodiments, the joint compound can comprise synthetic wax atabout 0.1% to about 8% of the joint compound dry weight.

In some embodiments, the joint compound can comprise wax emulsion andsilicones, or siloxanes, or siliconates, or fluorinated compounds, orstearates, or combinations thereof.

In some embodiments, the joint compound can comprise wax emulsion, thewax emulsion can be formed by mixing a combination of water, polyvinylalcohol, and paraffin wax, or montan wax, or synthetic wax, orcombinations thereof.

In some embodiments, an acid is not used in forming the water-resistantjoint compound. In some embodiments, the joint compound can have acontact angle of about 60 to about 130 degrees.

In some embodiments, the joint compound can further comprise about 5.89wt. % latex binder, about 34.60 wt. % water, about 7.36 wt. % waxemulsion, about 1.84 wt. % attapulgite clay, about 7.36 wt. % mica,about 33.86 wt. % calcium carbonate, and about 8.47 wt. % expandedperlite.

In some embodiments, the wax emulsion can further comprise about 58 wt.% water, about 2.70 wt. % polyvinyl alcohol, about 34.30 wt. % paraffinwax, and about 3.50 wt. % montan wax.

In some embodiments, the joint compound can comprise a wax emulsion andsilicones, or siliconates, or fluorinated compounds, or stearates, orcombinations thereof. In some embodiments, the silicones, siliconates,fluorinated compounds, or stearates can be selected from the groupconsisting of metal siliconate salts, potassium siliconate, polyhydrogen methyl siloxane, polydimethyl siloxane, stearate-based salts,and combinations thereof.

In some embodiments, the joint compound can comprise the wax emulsion,and at least one siliconate and optionally at least one thickener,preferably a cellulose ether based thickener.

BRIEF DESCRIPTION OF THE DRAWINGS

The disclosed aspects will hereinafter be described in conjunction withthe appended drawings, provided to illustrate and not to limit thedisclosed aspects, wherein like designations denote the elements.

FIG. 1 illustrates an example process of one embodiment of thedisclosure.

FIG. 2 illustrates a wall having an example embodiment of the disclosedwater-resistant joint compound applied thereon.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Embodiments of the present disclosure provide a water-resistant jointcompound formed from a wax emulsion. The joint compound may optionallybe used to create a water resistant barrier at wall joints, as well asat holes, such as nail holes, through a wall, thereby preventingmoisture from passing through the walls. The joint compound mayoptionally be used, for example, in construction of houses or commercialbuildings. The joint compound can contain, in some embodiments, a montanactivated and polyvinyl alcohol stabilized wax emulsion. By doing so,the resulting dried joint compound surface can exhibit a high contactangle, which can lead to exceptional water repellency. Further, thedisclosed joint compound formed from a wax emulsion can avoiddeleterious effects on key desirable performance properties of the jointcompound.

The joint compound can be used to create a moisture resistant jointcompound that can, for example, complement and be used on moistureresistant gypsum boards (“green” boards). These boards, along with thejoint compound, can be used in high humidity areas, such as bathrooms.The use of the moisture resistant boards and joint compounds can help toreduce the susceptibility of the walls, and the studs behind the walls,to mold growth and structural deformation caused through the absorptionof water, reducing damage and health risks.

Certain example embodiments of the joint compound can be generallyprepared from an improved wax emulsion, among other materials andadditives. More details on example embodiments of the differentmaterials are disclosed herein.

Wax Emulsions Including Moisture Resistant Stabilizers

Embodiments of an improved wax emulsion for use in a water-resistantjoint compound are now described in greater detail, as follows. Anembodiment of the wax emulsion may comprise water, a base, one or morewaxes optionally selected from the group consisting of slack wax,paraffin wax, and a polymeric stabilizer, such as ethylene-vinylalcohol-vinyl acetate terpolymer or polyvinyl alcohol. Further, montanwax, carnauba wax, sunflower wax, tall oil, tallow wax, rice wax, andany other natural or synthetic wax or emulsifiers containing organicacids (such as, for example, stearic acid) and/or esters can be used toform the wax emulsion.

Water may be provided to the emulsion, for example in amounts of about30% to about 60% by weight of the emulsion. The solids content of thewax emulsion can be about 40% to about 70% by weight of the emulsion.Other amounts may be used.

In some embodiments, a dispersant and/or a surfactant may be employed inthe improved wax emulsions. Optional dispersants, include, but are notlimited to those having a sulfur or a sulfur-containing group(s) in thecompound such as sulfonic acids (R—S(═O)2-OH) and their salts, whereinthe R groups may be otherwise functionalized with hydroxyl, carboxyl orother useful bonding groups. In some embodiments, higher molecularweight sulfonic acid compounds such as lignosulfonate, lignosulfonicacid, naphthalene sulfonic acid, the sulfonate salts of these acids andderivatized or functionalized versions of these materials are used inaddition or instead. An example lignosulfonic acid salt is Polyfon® Havailable from MeadWestvaco Corporation, Charleston, S.C. Otherdispersants may be used, such as magnesium sulfate, polycarboxylatetechnology, ammonium hepta molybdate/starch combinations, non-ionicsurfactants, ionic surfactants, zwitterionic surfactants and mixturesthereof, alkyl quaternary ammonium montmorillonite clay, etc. Similarmaterials may also be used, where such materials may be compatible withand perform well with the formulation components. For example, othermaterials may be used such that the edge swell, water absorption,internal bonding and/or flexural strength properties of the resultantboards are not materially affected and the resultant boards areacceptable for use as industry acceptable wallboard. If used, adispersant and/or surfactant may comprise about 0.01% to about 5.0% byweight of the improved wax emulsion formulation composition, preferablyabout 0.1% to about 2.0% by weight of the improved wax emulsionformulation composition. Other concentrations may be used.

The wax component of the emulsion may include at least one wax which maybe slack wax. The total wax content may be about 30% to about 60%, morepreferably about 30% to about 40% by weight of the emulsion. Slack waxmay be any suitable slack wax known or to be developed whichincorporates a material that is a higher petroleum refining fraction ofgenerally up to about 20% by weight oil. In addition to, or as analternative to slack wax, paraffin waxes of a more refined fraction arealso useful within the scope of the disclosure.

Suitable paraffin waxes may be any suitable paraffin wax, and preferablyparaffins of melting points of from about 40° C. to about 110° C.,although lower or higher melting points may be used if drying conditionsare altered accordingly using any techniques known or yet to bedeveloped in the composite board manufacturing arts or otherwise. Thus,petroleum fraction waxes, either paraffin or microcrystalline, and whichmay be either in the form of varying levels of refined paraffins, orless refined slack wax may be used. Optionally, synthetic waxes such asethylenic polymers or hydrocarbon types derived via Fischer-Tropschsynthesis may be included in addition or instead, however paraffins orslack waxes are preferred in certain embodiments. By way of furtherexample, synthetic waxes, such as polyethylene glycol,methoxypolyethylene glycol, or combinations thereof may be included. Anexample of a polyethylene glycol is PEG 1500, while an example ofmethoxypolyethylene glycol is MPEG 750 LD, both manufactured by ClariantInternational Ltd.

Montan wax, which is also known in the art as lignite wax, is a hard,naturally occurring wax that is typically dark to amber in color(although lighter, more refined montan waxes are also commerciallyavailable). Montan is insoluble in water, but is soluble in solventssuch as carbon tetrachloride, benzene and chloroform. In addition tonaturally derived montan wax, alkyl acids and/or alkyl esters which arederived from high molecular weight fatty acids of synthetic or naturalsources with chain lengths preferably of over 18 carbons, morepreferably from 26 to 46 carbons that function in a manner similar tonaturally derived montan wax are also within the scope of the disclosureand are included within the scope of “montan wax” as that term is usedherein unless the context indicates otherwise (e.g., “naturallyoccurring montan wax”). Such alkyl acids are generally described asbeing of formula R—COOH, where R is an alkyl non-polar group which islipophilic and can be from 18 to more than 200 carbons. An example ofsuch a material is octacosanoic acid and its corresponding ester whichis, for example, a di-ester of that acid with ethylene glycol. The COOHgroup forms hydrophilic polar salts in the presence of alkali metalssuch as sodium or potassium in the emulsion. While the alkyl portion ofthe molecule gets embedded within the paraffin, the acid portion is atthe paraffin/aqueous medium interface, providing stability to theemulsion. Other components which may be added include esterifiedproducts of the alkyl acids with alcohols or glycols.

In some embodiments, the at least one wax component of the emulsionincludes primarily and, preferably completely a slack wax component. Insome embodiments, the at least one wax component is made up of acombination of paraffin wax and montan wax or of slack wax and montanwax. Although it should be understood that varying combinations of suchwaxes can be used, and the combinations are not limiting. When usingmontan wax in combination with one or more of the other suitable waxcomponents, it is preferred that montan be present in an amount of about0.1% to about 10%, more preferably about 1% to about 4% by weight of thewax emulsion with the remaining wax or waxes present in amounts of fromabout 30% to about 50%, more preferably about 30% to about 35% by weightof the wax emulsion.

In some embodiments, the wax emulsion can include polyvinyl alcohol(PVOH) of any suitable grade which is at least partially hydrolyzed. Thepreferred polyvinyl alcohol is at least 80%, and more preferably atleast 90%, and most preferably about 97-100% hydrolyzed polyvinylacetate. Suitably, the polyvinyl alcohol is soluble in water at elevatedtemperatures of about 60° C. to about 95° C., but insoluble in coldwater. The hydrolyzed polyvinyl alcohol is preferably included in theemulsion in an amount of up to about 5% by weight, preferably 0.1% toabout 5% by weight of the emulsion, and most preferably about 2% toabout 3% by weight of the wax emulsion.

In some embodiments, the stabilizer comprises a polymer that is capableof hydrogen bonding to the carboxylate or similar moieties at thewater/paraffin interface. Polymers that fit the hydrogen-bondingrequirement would have such groups as hydroxyl, amine, and/or thiol,amongst others, along the polymer chain. Reducing the polymer's affinityfor water (and thus, its water solubility) could be achieved byinserting hydrophobic groups such as alkyl, alkoxy silanes, or alkylhalide groups into the polymer chain. The result may be a polymer suchas ethylene-vinyl acetate-vinyl alcohol terpolymer (where the vinylacetate has been substantially hydrolyzed). The vinyl acetate contentmay be between 0% to 15%. In some embodiments, the vinyl acetate contentis between 0% and 3% of the terpolymer chain. The ethylene-vinylalcohol-vinyl acetate terpolymer may be included in the emulsion in anamount of up to about 10.0% by weight, preferably 0.1% to about 5.0% byweight of the emulsion. In some embodiments, ethylene-vinylalcohol-vinyl acetate terpolymer may be included in the emulsion in anamount of about 2% to about 3% by weight of the wax emulsion. An exampleethylene-vinyl alcohol-vinyl acetate terpolymer that is available is theExceval AQ4104™, available from Kuraray Chemical Company.

The wax emulsion may include a stabilizer material (e.g., PVOH,ethylene-vinyl alcohol-vinyl acetate terpolymer as described above). Thestabilizer may be soluble in water at elevated temperatures similar tothose disclosed with reference to PVOH (e.g., about 60° C. up to about95° C.), but insoluble in cold water. The active species in the waxcomponent (e.g., montan wax) may be the carboxylic acids and esters,which may comprise as much as 90% of the wax. These chemical groups maybe converted into carboxylate moieties upon hydrolysis in a high pHenvironment (e.g., in an environment including aqueous KOH). Thecarboxylate moieties may act as a hydrophilic portion or “head” of themolecule. The hydrophilic portions can directly interface with thesurrounding aqueous environment, while the rest of the molecule, whichmay be a lipophilic portion or “tail”, may be embedded in the wax.

A stabilizer capable of hydrogen bonding to carboxylate moieties (e.g.,PVOH or ethylene-vinyl alcohol-vinyl acetate terpolymer as describedabove) may be used in the wax emulsion. The polar nature of thecarboxylate moiety may offer an optimal anchoring point for a stabilizerchain through hydrogen bonding. When stabilizer chains are firmlyanchored to the carboxylate moieties as described above, the stabilizermay provide emulsion stabilization through steric hindrance. Inembodiments where the wax emulsion is subsequently dispersed in awallboard (e.g., gypsum board) system, all the water may be evaporatedaway during wallboard manufacture. The stabilizer may then function as agate-keeper for repelling moisture. Decreasing the solubility of thestabilizer in water may improve the moisture resistance of the waxemulsion and the wallboard. For example, fully hydrolyzed PVOH may onlydissolve in heated, and not cool, water. For another example,ethylene-vinyl alcohol-vinyl acetate terpolymer may be even less watersoluble than PVOH. The ethylene repeating units may reduce the overallwater solubility. Other stabilizer materials are also possible. Forexample, polymers with hydrogen bonding capability such as thosecontaining specific functional groups, such as alcohols, amines, andthiols, may also be used. For another example, vinyl alcohol-vinylacetate-silyl ether terpolymer can be used. An example vinylalcohol-vinyl acetate-silyl ether terpolymer is Exceval R-2015,available from Kuraray Chemical Company. In some embodiments,combinations of stabilizers are used.

In some embodiments, the wax emulsion comprises a base. For example, thewax emulsion may comprise an alkali metal hydroxide, such as potassiumhydroxide or other suitable metallic hydroxide, such as aluminum,barium, calcium, lithium, magnesium, sodium, r zinc hydroxide, and/ormetal siliconates. These materials may serve as saponifying agents.Non-metallic bases such as derivatives of ammonia as well as amines(e.g., monoethanoline, diethanol or triethanol amine) can also be used.In some embodiments, potassium siliconate or imidazole could be used asa base. Combinations of the above-mentioned materials are also possible.If included in the wax emulsion, potassium hydroxide is preferablypresent in an amount of 0% to 1%, more preferably about 0.1% to about0.5% by weight of the wax emulsion.

In some embodiments, an exemplary wax emulsion comprises: about 30% toabout 60% by weight of water; about 0.1% to about 5% by weight of alignosulfonic acid or a salt thereof; about 0% to about 1% by weight ofpotassium hydroxide; about 30% to about 50% by weight of wax selectedfrom the group consisting of paraffin wax, slack wax and combinationsthereof; and about 0.1% to about 10% montan wax, and about 0.1 to 5% byweight of ethylene-vinyl alcohol-vinyl acetate terpolymer.

The wax emulsion may further include other additives, including withoutlimitation additional emulsifiers and stabilizers typically used in waxemulsions, flame retardants, lignocellulosic preserving agents,fungicides, insecticides, biocides, waxes, sizing agents, fillers,binders, additional adhesives and/or catalysts. Such additives arepreferably present in minor amounts and are provided in amounts whichwill not materially affect the resulting composite board properties.Preferably no more than 30% by weight, more preferably no more than 10%,and most preferably no more than 5% by weight of such additives arepresent in the wax emulsion.

Shown in the below Table I is an example embodiments of a wax emulsion,although other quantities in weight percent may be used.

TABLE I Example Wax Emulsion Composition Raw Material Quantity in WeightPercent Water 58 Polyvinyl alcohol 2.70 Dispersant 1.50 (Optional)Paraffin Wax 34.30 Montan Wax 3.50 Biocide 0.02

Table II below shows another example of a wax emulsion. In thisembodiment, stearic acid is used in place of montan wax.

TABLE II Example Wax Emulsion Composition Raw Material Quantity inWeight Percent Water 50.48% Polyvinyl alcohol  3.06% Monoethanol amine 0.08% Paraffin Wax 44.96% Stearic Acid  0.08% Biocide  0.02%

The wax emulsion may be prepared using any acceptable techniques knownin the art or to be developed for formulating wax emulsions, forexample, the wax(es) are preferably heated to a molten state and blendedtogether (if blending is required). A hot aqueous solution is preparedwhich includes any additives such as emulsifiers, stabilizers, etc.,ethylene-vinyl alcohol-vinyl acetate terpolymer (if present), potassiumhydroxide (if present) and lignosulfonic acid or any salt thereof. Thewax is then metered together with the aqueous solution in appropriateproportions through a colloid mill or similar apparatus to form a waxemulsion, which may then be cooled to ambient conditions if desired.

In some embodiments, the improved wax emulsion may be incorporated withor coated on various surfaces and substrates. For example, the improvedwax emulsion may be mixed with gypsum to form a gypsum wallboard havingimproved moisture resistance properties.

For a general understanding of an example embodiment of the method ofmaking the composition of the disclosure, reference is made to the flowdiagram in FIG. 1. As shown in 101, first the wax components may bemixed in an appropriate mixer device. Then, as shown in 102, the waxcomponent mixture may be pumped to a colloid mill or homogenizer. Asdemonstrated in 103, in a separate step, water, and any emulsifiers,stabilizers, or additives (e.g., ethylene-vinyl alcohol-vinyl acetateterpolymer) are mixed. Then the aqueous solution is pumped into acolloid mill or homogenizer in 104. Steps 101 and 103 may be performedsimultaneously, or they may be performed at different times. Steps 102and 104 may be performed at the same time, so as to ensure properformation of droplets in the emulsion. In some embodiments, steps 101and 102 may be performed before step 103 is started. Finally, as shownin 105, the two mixtures from 102 and 104 are milled or homogenized toform an aqueous wax emulsion.

Some or all steps of the above method may be performed in open vessels.However, the homogenizer, if used, may use pressure in its application.

Advantageously in some embodiments, the emulsion, once formed, is cooledquickly. By cooling the emulsion quickly, agglomeration and coalescenceof the wax particles may be avoided.

In some embodiments the wax mixture and the aqueous solution arecombined in a pre-mix tank before they are pumped into the colloid millor homogenizer. In other embodiments, the wax mixture and the aqueoussolution may be combined for the first time in the colloid mill orhomogenizer. When the wax mixture and the aqueous solution are combinedin the colloid mill or homogenizer without first being combined in apre-mix tank, the two mixtures may advantageously be combined underequivalent or nearly equivalent pressure or flow rate to ensuresufficient mixing.

In some embodiments, once melted, the wax emulsion is quickly combinedwith the aqueous solution. While not wishing to be bound by any theory,this expedited combination may beneficially prevent oxidation of the waxmixture.

Water-Resistant Joint Compound

Embodiments of the disclosed wax emulsion can be used to form awater-resistant joint compound. The joint compound can be used to cover,smooth, or finish gaps in boards, such as joints between adjacentboards, screw holes, and nail holes. The joint compound can also be usedfor repairing surface defects on walls and applying texture to walls andceilings amongst numerous other applications. The joint compound canalso be specially formulated to serve as a cover coat on cement andconcrete surfaces. The joint compound can be particularly useful inlocations where there is high humidity, such as bathrooms, to preventmolding or other deleterious effects.

Wax emulsions can be particularly advantageous for use in a jointcompound as compared to, for example, non-emulsified and/ornon-stabilized waxes such as melted PEG M750. These non-emulsified waxescan impart severe deleterious effects on the adhesion properties of ajoint compound. Therefore, if the non-emulsified wax is to be used atall, it must be added in very low levels. On the other hand, waxemulsions, such as those described herein, can advantageously increasethe adhesion properties of a joint compound, at least due to theadhesive effects of the stabilizer, and thus can be added at higherdosage levels. The wax emulsions can then be useful as they can provideboth low dust properties as well as water repellency to the jointcompound. In some embodiments, the wax emulsion can act as a dedustingagent. The wax emulsion can soften or melt when friction is applied,such as during cutting or sanding. Accordingly, dust can be agglomeratedby the softened wax emulsion, where it can be securely held.

Embodiments of the joint compound can be applied in thin layers to asurface. The joint compound can be applied by, for example, using atrowel or other straight edged tool. However, the application andthickness of the layers of joint compounds is not limiting. Further,multiple layers may be applied in order to obtain a smooth, attractivefinished wall. The number or layers applied is not limiting. In someembodiments, each layer can be allowed to dry prior to application ofthe next layer. In some embodiments, a second layer can be applied whenthe first layer is only partially dried. In some embodiments, the jointcompound can be spread over mesh or tape used to connect wallboards. Insome embodiments, the joint compound may also be used to patch andtexture interior walls. In some embodiments, the joint compound can bemade of water, preservative, calcium carbonate, mica, clay, thickener,binder (e.g., latex binder), and a wax emulsion. In addition to a latexbinder, other water soluble binders, such as polyvinyl alcohol, can beused as well. Other materials, such as talc, binders, fillers,thickening agents, preservatives, limestone, perlite, urea, defoamingagents, gypsum latex, glycol, and humectants can be incorporated intothe joint compound as well or can substitute for certain ingredients(e.g., talc can be used in place of, or in addition to mica; gypsum canbe used in place of, or in addition to calcium carbonate, etc.). In someembodiments, the calcium carbonate can be replaced either wholly orpartially with a surface micro-roughened filler that can further enhancethe joint compound's hydrophobicity. In some embodiments, Calcimatt™,manufactured by Omya AG, can be used. In some embodiments, cristobalite(silicon dioxide) such as Sibelite® M3000, manufactured by Quarzwekre,can be used. These fillers can be used alone or in combination.

In some embodiments, the joint compound can be mixed in water. Thismixture can then be applied to a surface, e.g., hole or joint, and canbe allowed to dry. Once the water evaporates from the mixture, a dry,relatively hard cementitious material can remain. In some embodiments,shrinkage may occur upon drying.

FIG. 2 shows an example of a wall system incorporating an embodiment ofa water-resistant joint compound. As shown, the wall system can be madeof a plurality of boards 202. There is no limit to the amount of boardsor the positioning of boards next to one another. Where two boards 202are adjacent to one another, a gap, or joint, can be formed. While theboards 202 themselves may be water-resistant, the joints may allow formoisture to pass through. Therefore, embodiments of the water-resistantjoint compound 204 can be spread across the joints. The compound 204 canbe spread on the joint to completely cover the joint. In someembodiments, the boards 202 can also contain holes. These holes can beformed by nailing the boards 202 into studs, or other attachment means.Regardless of the reason for the hole, the compound 206 can also be usedto cover the holes. The compound 206 can insert partial through theholes, or can cover the top of the holes, or both. The compound 206 cancover any fastener, e.g. a screw or nail, that is located in the hole.In some embodiments, compound 206 and 204 are the same compound. Theapplication and thickness of the compound 204/206 on the boards 202 isnot limiting, and common methods of application can be used.

An example formula range of an embodiment of a water-resistant jointcompound using the above disclosed wax is shown in the below Table III:

TABLE III Example Composition of a Water-Resistant Joint CompoundComponent Range Water  20-55% Preservatives  0.02-1.0%  CalciumCarbonate  10-50% Mica 0.5-10% Attapulgite Clay 0.2-10% Talc 0.0-10%Perlite 0.0-40% Polyethylene oxide 0.0-10% Polyether siloxane 0.0-10%Wax emulsion 0.1-20% Latex binder 0.5-10% Cellulose ether thickener0.1-8.0% 

Further, an example of a specific formulation for a water-resistantjoint compound can is shown in the below Table IV, although other weightpercentages may be used:

TABLE IV Example Composition of a Water-Resistant Joint CompoundCompound Wt. % Preservative 0.01 Wetting Agent 0.05 Latex Binder 5.89Water 34.60 Wax emulsion 7.36 Cellulose ether 0.55 Attapulgite clay 1.84Mica 7.36 Calcium Carbonate 33.86 Expanded Perlite 8.47

Another embodiment of a water-resistant ready-mix joint compound formulais shown in the below Table V. In this embodiment, an optional potassiumsiliconate additive is incorporated.

TABLE V Raw Material Wt. % Preservative 0.20% Latex (CPS 716) 6.50%Water 36.70%  Wax Emulsion 3.80% Potassium Siliconate (Silres BS 16)0.20% Cellulose Ether 0.60% Clay (Attagel 30) 1.90% Mica 6.10% Limestone(MW 100) 35.20%  SilCel 43-34 8.80%

The wax emulsion used in the joint compound can be formed from slackwax, montan wax, paraffin wax, carnauba wax, tall oil, sunflower wax,rice wax, and any other natural or synthetic wax containing organicacids and/or esters, or combinations thereof. For example, synthetic waxused in the joint compound may comprise ethylenic polymers orhydrocarbon types, optionally derived via Fischer-Tropsch synthesis, orcombinations thereof. By way of further example, synthetic wax used inthe joint compound may comprise polyethylene glycol, methoxypolyethyleneglycol, or combinations thereof. Optionally, the synthetic waxes can beadded in concentrations ranging from about 0.1% to about 8% of the dryweight of the joint compound or from about 0.5% to about 4.0% of the dryweight of the joint compound. In some embodiments, the wax emulsion isstabilized by polyvinyl alcohol.

In some embodiments, perlite can be used in a joint compound to, forexample, control the density, shrinkage, and crack resistance of thejoint compound. In some embodiments, perlite need not be used (e.g.,where weight is not as much of a factor).

In some embodiments, mica can be used in a compound as well. Mica, whichis a low bulk density mineral, may be used as a filler or extender, andmay also improve crack resistance of the joint compound.

In some embodiments of the joint compound gypsum (calcium sulfatedihydrate) can also be used. Gypsum can be used to replace calciumcarbonate, or can be used in conjunction with calcium carbonate. In someembodiments, talc can be included in a joint compound to, for example,enhance application properties and can also be used as a white extenderpigment.

In some embodiments, clay can be used in a joint compound as, forexample, a non-leveling agent and/or a thickening agent that can controlthe viscosity or rheology of the final product. Clay can also helpenhance or create the water-holding properties of the joint compound.

In some embodiments, thickeners can be used to control the viscosity,affect the rheology, and affect the water holding characteristics of ajoint compound. For example, cellulose ether can be used as a thickener.

In some embodiments, binders can be used in a joint compound to, forexample, improve bonding to the substrate such as wallboard.

In some embodiments, a glycol can be used in a joint compound to providefunctional properties to the joint compound such as wet edge, open time,controlling drying time, and freeze/thaw stability.

In some embodiments, other rheology modifiers can also be used inconjunction with, or instead of, some of the above describedcompositions.

In some embodiments, fillers can be used in the joint compound. Forexample, calcium carbonate, calcium sulfate hemihydrate, or calciumsulfate dehydrate can all be used as fillers, though other materials canbe used as well. Further, thickeners, preservatives, binders, and otheradditives can be incorporated into the joint compound.

Other additives can also be added to the described joint compound inaddition to the wax emulsion. In some embodiments, metal siliconatesalts such as, for example, potassium siliconate, as well as siliconebased compounds such as, for example, poly hydrogen methyl siloxane andpolydimethyl siloxane, could provide advantageous water resistance to ajoint compound. In some embodiments, fluorinated compounds andstearate-based salts could also be used to provide advantageous waterresistance.

Any suitable siliconate may be used. Suitable examples of siliconatesinclude, but are not necessarily limited to, NaOSi(OH)2(CH2)3NH2,NaO(OH)Si(CH3)(CH2)3NH2, KO0.5(HO)1.5Si(CH3)(CH2)3NH2,KOSi(OH)2(CH2)3NH2, LiO(OH)Si(CH3)(CH2)3NH2, and KO(HO)Si(CH3)(CH2)3NH2.Such siliconates are discussed in U.S. Pat. App. No. 20070028809 toWacker et al, which is incorporated fully by reference herein.

In at least one embodiment, the siliconate is provided in an aqueoussolution which is then mixed into the joint compound formulation. Thesiliconate solids in such aqueous solution is from about 10-70% byweight. In these embodiments, the siliconate may be present in the jointcompound formulation in an amount of 0.010% to about 5%, based on thetotal weight of the joint compound formulation (on a dry basis, that isafter the joint compound has been applied and dried). Stated anotherway, the siliconate may be present in the joint compound in an amountdefined by any one of following numbers, by weight of the dried jointcompound:

0.01, 0.02, 0.03, 0.04, 0.05, . . . 0.0.10, . . . , 0.20, . . . , 1.0, .. . , 2.0, . . . 5.0.

The siliconate can also be in an amount within a range defined by anytwo numbers above, including the endpoints.

In one embodiment, the latex binder used in the joint compound rangesfrom about 0.5 to about 10 wt. %. Stated another way, the latex bindermay be present in the joint compound in an amount defined by any one offollowing numbers, by weight of the joint compound:

-   -   0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7,        1.8, 1.9, 2.0, 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3.0,        3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4.0, 4.1, 4.2, 4.3,        4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5.0, 5.1, 5.2, 5.3, 5.4, 5.5, 5.6,        5.7, 5.8, 5.9, 6.0, 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9,        7.0, 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 8.0, 8.1, 8.2,        8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9.0, 9.1, 9.2, 9.3, 9.4, 9.5,        9.6, 9.7, 9.8, 9.9, and 10.0.

The latex binder can also be in an amount within a range defined by anytwo numbers above, including the endpoints. With the joint compoundpreparation above, this invention allows for a very small amount oflatex binder being included in the joint compound but without anyadverse impact to the physical characteristics of the joint compound.For example, the water repellency in fact improved for a joint compoundin which the latex binder content was reduced. For example, in sample 3(Table 1), 5.8% latex binder was used with 0.2% potassium siliconate,the contact angle was 91 and the Cobb value was 69. When the bindercontent was reduced to 4.0% by weight of the joint compound, the contactangle improved 20%, to 110, and the Cobb value by more than 95%. In oneembodiment, the present invention envisions reducing the latex bindercontent progressively to achieve the desired contact angle as well asthe Cobb value.

In at least one embodiment, the joint compound may comprise a celluloseether, for example, a hydroxy-based cellulose ether. In at least oneembodiment, the cellulose ether is present in the joint compound in anamount of 0.050 to 3.0 weight percent, based on the total weight of thejoint compound. Stated another way, the cellulose ether may be presentin the joint compound in an amount defined by any one of followingnumbers, by weight of the dried joint compound:

0.05, . . . 0.0.10, . . . , 0.20, . . . , 1.0, . . . , 2.0, . . . , 3.0.

The cellulose ether can also be in an amount within a range defined byany two numbers above, including the endpoints.

Any suitable cellulose ether may be used. Suitable examples ofhydroxy-based cellulose ethers include, but are not necessarily limitedto, hydroxyethyl cellulose ether, hydroxypropyl cellulose ether,hydroxyethyl methyl cellulose ether, hydroxypropyl methyl celluloseether, carboxymethyl cellulose ether, methyl hydroxy cellulose ether,hydroxymethyl cellulose ether, and methylhydroxyethyl cellulose ether.

In at least one embodiment, suitable cellulose ether, for example,hydroxy-based cellulose ethers have a molecular weight of from 50,000 to500,000, and preferably from 75,000 to 150,000, with a chain length offrom 300 to 1500 repeating units, and more preferably from 400 to 700.Stated another way, the molecular weight of the cellulose ether can beany one of the following numbers:

-   -   50,000; 60,000; 70,000; 80,000; 90,000; 100,000; 110,000;        120,000; 130,000; 140,000; 150,000; 160,000; 170,000; 180,000;        190,000; 200,000; 210,000; 220,000; 230,000; 240,000; 250,000;        260,000; 270,000; 280,000; 290,000; 300,000; 310,000; 320,000;        330,000; 340,000; 350,000; 360,000; 370,000; 380,000; 390,000;        400,000; 410,000; 420,000; 430,000; 440,000; 450,000; 460,000;        470,000; 480,000; 490,000; and 500,000.

The molecular weight of the cellulose ether can also be within a rangedefined by any two numbers above, including the endpoints.

The cellulose ethers, for example, hydroxy-based cellulose ethers shouldalso have a viscosity range of from 1000 to 100,000 cps, and morepreferably from 2000 to 10,000 cps, as measured by 2% solution in waterat 20° C., according to ASTM D 2363. Stated another way, the viscosityof the cellulose ether can be any one of the following numbers, measuredin cp units:

-   -   1,000; 2,000; 3,000; 4,000; 5,000; 6,000; 7,000; 8,000; 9,000;        10,000; 11,000; 12,000; 13,000; 14,000; 15,000; 16,000; 17,000;        18,000; 19,000; 20,000; 21,000; 22,000; 23,000; 24,000; 25,000;        26,000; 27,000; 28,000; 29,000; 30,000; 31,000; 32,000; 33,000;        34,000; 35,000; 36,000; 37,000; 38,000; 39,000; 40,000; 41,000;        42,000; 43,000; 44,000; 450,000; 46,000; 47,000; 48,000; 49,000;        50,000; 51,000; 52,000; 53,000; 54,000; 55,000; 56,000; 57,000;        58,000; 59,000; 60,000; 61,000; 62,000; 63,000; 64,000; 65,000;        66,000; 67,000; 68,000; 69,000; 70,000; 71,000; 72,000; 73,000;        74,000; 75,000; 76,000; 77,000; 78,000; 79,000; 80,000; 81,000;        82,000; 83,000; 84,000; 85,000; 86,000; 87,000; 88,000; 89,000;        90,000; 91,000; 92,000; 93,000; 94,000; 950,000; 96,000; 97,000;        98,000; 99,000; and 100,000.

The molecular weight of the cellulose ether can also be within a rangedefined by any two numbers above, including the endpoints.

Hydroxy-based cellulose ethers such as these are normally identified bytheir viscosity rather than molecular weight.

In at least one embodiment, the cellulose ether is methyl celluloseether, for example Methocel® manufactured by Dow Chemical Co. Methocel®products are available in two basic types: methylcellulose andhydroxypropyl methyl cellulose ether. Both types of Methocel have thepolymeric backbone of cellulose, a natural carbohydrate that containsbasic repeating structure of anhydroglucose units. Methylcellulose etheris made using only methyl chloride. Hydroxypropyl methylcellulose etheruses propylene oxide in addition to methyl chloride to obtainhydroxypropyl substitution on the anhydroglucose units. This substituentgroup, —OCH2CH(OH)CH3-, contains a secondary hydroxyl on the number twocarbon and may be considered to form a propylene glycol ether ofcellulose. These products possess varying ratios of hydroxypropyl andmethyl substitution. The amount of substituent groups on theanhydroglucose units of cellulose can be designated by weight percent orby the average number of substituent groups attached to the ring, aconcept known to cellulose chemists as “degree of substitution” (DS).

If all three available positions on each unit are substituted, the DS isdesignated as 3; if an average of two on each ring are reacted, the DSis designated as 2, etc. The number of substituent groups on the ringdetermines the properties of the various products. For example,Methocel® A cellulose ether contains 27.5 to 31.5% methoxyl, or amethoxyl DS of 1.64 to 1.92, a range that yields maximum watersolubility. A lower degree of substitution gives products having lowerwater solubility, leading to products that are only soluble in causticsolutions. Higher degrees of substation produce methylcellulose productsthat are soluble only in organic solvents. In the Methocel E, F and Kcellulose ether products, the methoxy substitution is still the majorconstituent. The molar substitution (MS) reports the number of moles ofhydroxypropyl groups per mole of anhydroglucose. In the Methocel J and310 series products, the hydroxypropyl substitution is about 50% of thetotal substitution. All these soluble methyl cellulose ethers can beused in embodiments of the present invention.

TABLE 1 Siliconate containing water resistant joint compound formulasBatch ID Control 1 2 3 4 Acticide 0.1 0.1 0.1 0.1 0.1 CBM2 Fungitrol0.11 0.1 0.1 0.1 0.1 404DS Latex CPS 8.2 5.9 5.8 4.7 4.0 716 Water 40.840.4 37.3 37.7 38.0 Wax Emulsion — — 3.1 3.1 3.1 AQ484 Potassium — 1 0.20.2 0.2 siliconate (Silres BS 16) Cellulose ether 0.5 0.6 0.4 0.4 0.4(MOT 60000 YP4) Cellulose ether — — 0.2 0.2 0.2 (Methocel 240S) Attagel30 1.8 1.9 1.9 2.0 2.0 4K Mica 7.2 7.4 6.2 6.3 6.3 Calcium 33 34.1 35.736.1 36.4 carbonate (Imerys MW 100) Expanded 8.2 8.5 8.9 9.0 9.1 perlite(SilCel 43-34) Total wt. 100 100 100 100 100 Total solids 54.9 55.6 56.356.5 56.5 % Solids 54.91% 55.55% 56.30% 56.45% 56.50% % Active 0 0.34%0.07% 0.07% 0.07% siliconate in wet compound % Active 0 0.61% 0.12%0.12% 0.12% siliconate in dry compound Wt. fraction of 0 0 2.2% 2.2%2.2% wax solids in dry compound Joint 0 86 91 98 110 compound contactangle Cobb values 69 7 3 (unsanded, 30 mins.) Cobb values 482 24 8 1(sanded, 30 mins.)

In some embodiments, the wax emulsion can be replaced by other materials(or used in combination with other materials) which may also increasethe water repellency of the joint compound. For example, metalsiliconate salts such as, for example, potassium siliconate, as well assilicone based compounds such as, for example, poly hydrogen methylsiloxane and polydimethyl siloxane, could be used in place of the waxemulsion (or in combination with the wax emulsion). In some embodiments,fluorinated compounds and stearate-based salts could also be usedinstead of the wax emulsion or in combination with the wax emulsion. Thecompounds described in this paragraph can be used alone as a replacementfor wax emulsion, or can be used in combination with each other.

In some embodiments, the disclosed joint compound can cover a joint orhole and provide resistance to water penetration. Further, the jointcompound is formulated to properly adhere to any boards that thecompound is placed onto. With regards to adhesion, embodiments of thejoint compound can have at least about 90%, 95%, 99%, or 100% bondaccording to an ASTM C474 peel test, hereby incorporated by reference inits entirety. Further, the joint compound can have adequate sagresistance, compatibility, and contact angle.

In some embodiments, the joint compound can provide water repellency.One indication of water repellency is the contact angle of a waterdroplet on the surface of the dried joint compound. A water dropletsurface that has a contact angle of less than 90 degrees would generallybe considered hydrophilic (the smaller the contact angle the greater thehydrophilicity). Conversely, surfaces that cause a water droplet to havea contact angle greater than 90 degrees are generally consideredhydrophobic. Commercially available ready mix joint compound havecontact angles of about zero degrees, meaning that a drop of waterplaced on such a surface will rapidly spread and wet out on the surface.Embodiments of the disclosed joint compound can have a contact anglegreater than about 60, 70, 80, 90, 100, 110, 120, or 130. In someembodiments, the joint compound can have a contact angle between about60 and 130, about 115 and 130, or about 118-120. Embodiments of thedisclosed joint compound, containing a wax emulsion, can have an averagecontact angle of about 98 degrees (based on an average of sixmeasurements), or greater than about 98 degrees, indicating ahydrophobic surface.

In some embodiments, the contact angle can be between about 60 to about110 degrees, or about 60, about 70, about 80, about 90, about 100, orabout 110 degrees.

In some embodiments, the contact angel can be any number selected fromthe following numbers in degrees:

-   -   60, 61, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76,        77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92,        93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106,        107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119,        120, 121, 122, 123, 124, 125, 126, 127, 128, 129, and 130.

The contact angle can also be within a range defined by any two numbersabove, including the endpoints.

This contact angle value can be modified, higher or lower, by adjustingthe dosage level of the wax emulsion in the joint compound formula.

In some embodiments, the disclosed joint compound can be resistant toseepage of water into itself. This attribute can be generally determinedby measuring the Cobb value of the compound. A Cobb value is aquantitative determination of how much water a substrate absorbs in apredetermined timeframe. For example, a leveled surface of an embodimentof the disclosed joint compound was applied on to a piece ofcommercially available regular ½″ gypsum wallboard. When dried, thejoint compound was sanded to a uniform ¼″ thickness above the wallboard.A 100 cm2 Cobb testing ring was then fitted on top of the joint compoundand the ring filled with 100 grams of water to begin the test. After twohours, the water was discarded and the Cobb ring disassembled. Thewallboard/joint compound combo was then weighed to determine how muchwater was absorbed. This gram weight of water was multiplied by 100 togive the Cobb value of water absorbed per square meter. For a controljoint compound (standard commercially available lightweight jointcompound), the 30 minute Cobb value was 1406 grams of water per squaremeter. Commercially available lightweight joint compounds can have 30minute Cobb values as high as 1600 grams per square meter. Forcomparison, the moisture resistant wallboard (“Green Board”) upon whichthe joint compound is applied has a 30 minute Cobb value of less than100. Hence, filling a joint with a joint compound with a Cobb valueseveral times higher than that of the corresponding wallboard caneffectively create a weak link. For more satisfactory protection of thewall system, the Cobb value of the joint compound can formulated to besimilar to that of the wallboard.

For further comparison, a joint compound formula containing 6.7% of thewax emulsion had a 30 minute Cobb value of about 65 grams per squaremeter, which is significantly less absorbing. In some embodiments thedisclosed joint compound can have a 30 minute Cobb value range ofbetween about 5.0 to about 200 grams per square meter, or about 5.0,about 10, about 20, about 30, about 40, about 50, about 100, about 150,or about 200 grams per square meter. In some embodiments, the disclosedjoint compound can have a 30 minute Cobb value range of less than about200, less than about 150, less than about 100, less than about 50, lessthan about 40, less than about 30, or less than about 20 grams persquare meter. In some embodiments, the disclosed joint compound can havea 30 minute Cobb value of about 50, about 100, about 150, about 200,about 300, about 400, or about 500 grams per square meter.

Water resistance of the joint compounds was also evaluated via anadapted/modified version of ASTM C473, hereby incorporated by referencein its entirety. In this method, a weighed sample is submerged in waterfor 2 hours after which it is taken out, excess water dabbed off andthen weighed again. The increase in weight after submersion representsthe amount of water absorbed by the sample. The less water that isabsorbed, the more water resistant the compound would be.

A metal ring of 2.5″ internal diameter (and ⅖″ internal height) wasplaced on a silicone coated paper (for non-stick). A sample ofconventional ready-mixed joint compound was then applied inside the ringsuch that it occupied the entire open volume of the ring. Theconventional joint compound was allowed to dry on a lab bench overnight,then transferred into a forced air oven at 50° C. where drying wascontinued for another 5 hours (until constant weight) to form a patty.The same procedure was performed with the disclosed wax emulsion jointcompound, forming a second patty. The patties were then lightly sandedall around (to ensure patty smoothness), weighed, and then submerged ina water bath in a manner similar to ASTM Method C473. To prevent sampleflotation when in the water, a 100 gram weight was placed on each samplethrough the duration of the test. As in ASTM C473, the joint compoundpatties were removed from the water bath after 2 hours, excess waterpatted off, and weighed. The results of the testing are shown in thebelow Table VI.

TABLE VI Testing Results % Water Joint compound absorption Samplecondition Sheetrock Lightweight Dust Control  32% Broke apart DisclosedJoint Compound with 6.7% 5.2% Maintained structural Wax Emulsion anddimensional integrity

While the commercial joint compound crumbled at the end of the test andcould not be reused or retested, the patty containing the disclosed waxemulsion joint compound retained its structural and dimensionalintegrity. The patty containing the disclosed wax emulsion was in factdried and then re-submerged to repeat the test. The second test gave avalue of 5.4% and a third submersion test on the same sample gave avalue of 4.0%. In some embodiments, the wax emulsion joint compound canhave a % water absorbance from about 4 to about 6. In some embodiments,the wax emulsion joint compound can have a % water absorbance of about 6or less, about 5.4 or less, about 5.2 or less, or about 4 or less. Thestructural and dimensional integrity of the wax emulsion containingpatty remained intact and unchanged through the third testing cycle,suggesting that it could continue to survive multiple cycles ofsubmersion and retesting. By contrast, the standard commerciallyavailable joint compound could not survive a single test cycle.

Standard joint compounds typically have a pH of 8-9, primarily as aresult of the high calcium carbonate content. However, it can beundesirable for the pH of joint compound to be much higher than 9.0because of the corrosive effects such high pH would have on worker'sfinishing tools as well as on the skin. Advantageously, the wax emulsionused in embodiments of the disclosed joint compound can have a pH ofbetween 7.0 and 8.0, meaning that adding it as a component in a jointcompound formulation does not result in an overall increase in the pH ofthe joint compound. This can advantageously be done without the additionof an acid. In some embodiments, an acid can be used. Accordingly, thepH of the joint compound can be about 7.0 or about 8.0, or below about9.0 or below about 8.0.

In some embodiments, once the joint compound is applied, the compoundmay be sanded. This sanding can be generally done to smooth out thefinish of the compound, or can be used to remove excess material.However, sanding of the joint compound can have an additional benefit inthat the sanding can increase the overall adherence of paint, or othercoating, onto the joint compound.

Water-Resistant Products

Embodiments of the disclosed wax emulsion can be used to form manydifferent water-resistant products. For example, embodiments of the waxemulsion can be incorporated into building materials such as asphalt(e.g., comprising a viscous liquid or semi-solid form of petroleum),concrete (e.g., comprising aggregate or filler, cement, water, variouschemical and/or mineral admixtures, etc.), stucco, cement (e.g., formedfrom or comprising calcium carbonate, clay, gypsum, fly ash, groundgranulated blast furnace slag, lime and/or other alkalis, airentrainers, retarders, and/or coloring agents) or other binders. In someembodiments, the wax emulsion can be incorporated into concrete covercoat formulations, such as those used for filling, smoothing, and/orfinishing interior concrete surfaces, drywall tape, bead embedment,skimcoating, and texturing drywall. Further, embodiments of the waxemulsion can be incorporated into concrete and/or cement mixtures as awater repellent additive. Therefore, embodiments of the wax emulsion canbe incorporated into pourable concrete and/or cement that can be used,for example, for foundations in home constructions. Additionally,embodiments of the wax emulsion can be used in cinder blocks as well asother similar concrete or cement based products. In some embodiments, awater-resistant building material can be formed with cement, and waxemulsion, or silicone, or siloxane, or siliconate, or fluorinatedcompound, or stearate, or combinations thereof.

Embodiments of the wax emulsion can also be incorporated into boards,such as cement boards (e.g., a relatively thin board, comprising cementbonded particle boards and cement fiber (e.g., comprising cement,fillers, cellulose, mica, etc.), which may be 0.25-0.5 inch thick orwhich may be thicker or thinner), and/or cement board formulations.Therefore, the wax emulsion can be used to provide additional waterresistance of the boards, and potentially prevent water or water vaporfrom penetrating the boards. In some embodiments, a water-resistantcement board can be formed with cement, and wax emulsion, or silicone,or siloxane, or siliconate, or fluorinated compound, or stearate, orcombinations thereof, wherein the combination of cement and waxemulsion, or silicone, or siloxane, or siliconate, or fluorinatedcompound, or stearate, or combinations thereof is formed into the shapeof a board.

Additionally, embodiments of the wax emulsion can be incorporated intopaint and/or paint formulations (e.g. a liquid, liquefiable, or masticcomposition that, after application to a substrate in a thin layer,converts to a solid film), such as paint that may be used to protect,color, or provide texture to a substrate. This can be done to impartwater repellency, or water resistance, to the paint. The type of paintis not limiting, and embodiments of the wax emulsion can be incorporatedinto oil, water, acrylic, or latex based paints, including paints thatmay be pigmented to add color to the substrate on which the paint isapplied. This water resistant paint can then be used on exterior andinterior surfaces of buildings, as well as other products such asvehicles (e.g. cars, boats, and planes), toys, furniture. In someembodiments, a water-resistant paint can be formed comprising paint andwax emulsion, or silicone, or siloxane, or siliconate, or fluorinatedcompound, or stearate, or combinations thereof.

From the foregoing description, it will be appreciated that inventivedevices and approaches for water resistant products and wax emulsionshave been disclosed. While several components, techniques and aspectshave been described with a certain degree of particularity, it ismanifest that many changes can be made in the specific designs,constructions and methodology herein above described without departingfrom the spirit and scope of this disclosure.

Certain features that are described in this disclosure in the context ofseparate implementations can also be implemented in combination in asingle implementation. Conversely, various features that are describedin the context of a single implementation can also be implemented inmultiple implementations separately or in any suitable subcombination.Moreover, although features may be described above as acting in certaincombinations, one or more features from a claimed combination can, insome cases, be excised from the combination, and the combination may beclaimed as any subcombination or variation of any subcombination.

Moreover, while methods may be depicted in the drawings or described inthe specification in a particular order, such methods need not beperformed in the particular order shown or in sequential order, and thatall methods need not be performed, to achieve desirable results. Othermethods that are not depicted or described can be incorporated in theexample methods and processes. For example, one or more additionalmethods can be performed before, after, simultaneously, or between anyof the described methods. Further, the methods may be rearranged orreordered in other implementations. Also, the separation of varioussystem components in the implementations described above should not beunderstood as requiring such separation in all implementations, and itshould be understood that the described components and systems cangenerally be integrated together in a single product or packaged intomultiple products. Additionally, other implementations are within thescope of this disclosure.

Conditional language, such as “can,” “could,” “might,” or “may,” unlessspecifically stated otherwise, or otherwise understood within thecontext as used, is generally intended to convey that certainembodiments include or do not include, certain features, elements,and/or steps. Thus, such conditional language is not generally intendedto imply that features, elements, and/or steps are in any way requiredfor one or more embodiments.

Conjunctive language such as the phrase “at least one of X, Y, and Z,”unless specifically stated otherwise, is otherwise understood with thecontext as used in general to convey that an item, term, etc. may beeither X, Y, or Z. Thus, such conjunctive language is not generallyintended to imply that certain embodiments require the presence of atleast one of X, at least one of Y, and at least one of Z.

Language of degree used herein, such as the terms “approximately,”“about,” “generally,” and “substantially” as used herein represent avalue, amount, or characteristic close to the stated value, amount, orcharacteristic that still performs a desired function or achieves adesired result. For example, the terms “approximately”, “about”,“generally,” and “substantially” may refer to an amount that is withinless than or equal to 10% of, within less than or equal to 5% of, withinless than or equal to 1% of, within less than or equal to 0.1% of, andwithin less than or equal to 0.01% of the stated amount.

Some embodiments have been described in connection with the accompanyingdrawings. The figures are drawn to scale, but such scale should not belimiting, since dimensions and proportions other than what are shown arecontemplated and are within the scope of the disclosed inventions.Distances, angles, etc. are merely illustrative and do not necessarilybear an exact relationship to actual dimensions and layout of thedevices illustrated. Components can be added, removed, and/orrearranged. Further, the disclosure herein of any particular feature,aspect, method, property, characteristic, quality, attribute, element,or the like in connection with various embodiments can be used in allother embodiments set forth herein. Additionally, it will be recognizedthat any methods described herein may be practiced using any devicesuitable for performing the recited steps.

While a number of embodiments and variations thereof have been describedin detail, other modifications and methods of using and medicalapplications for the same will be apparent to those of skill in the art.Accordingly, it should be understood that various applications,modifications, materials, and substitutions can be made of equivalentswithout departing from the unique and inventive disclosure herein or thescope of the claims.

What is claimed:
 1. A method of making a water-resistant joint compoundcomprising: mixing a combination of: water; a preservative; a waxemulsion wherein the wax emulsion comprises paraffin wax, montan wax,carnauba wax, sunflower wax, rice wax, tallow wax, synthetic wax, waxcontaining organic acids, wax containing esters, or combinationsthereof; at least one silicone, siliconate, fluorinated compound,stearate, or combinations thereof; and the wax emulsion is stabilizedwith polyvinyl alcohol and wherein the joint compound has a contactangle of about 60 to about 130 degrees; a pH below 12; and a Cobb valueof about 1.0 to about 200 grams per square meter.
 2. The method ofmaking the joint compound of claim 1, wherein the joint compoundcomprises: about 20 to about 55 wt. % water; about 0.02 to about 1.0 wt.% preservatives; about 0.1 to about 20 wt. % wax emulsion; and furthercomprises about 10 to about 50 wt. % calcium carbonate; about 0.0 toabout 10 wt. % mica; about 0.0 to about 10 wt. % attapulgite clay; about0.0 to about 10 wt. % talc; about 0.0 to about 40 wt. % perlite; about0.0 to about 10 wt. % polyethylene oxide; about 0.0 to about 10 wt. %polyether siloxane; about 0.5 to about 10 wt. % latex binder; and about0.1 to about 8.0 wt. % cellulose ether thickener.
 3. The method ofmaking the joint compound of claim 1, wherein the joint compound furthercomprises a rheology modifier, a binder, a thickener, and a filler. 4.The method of making the joint compound of claim 1, wherein the jointcompound further comprises calcium carbonate, cristobalite, amicro-roughened filler, gypsum, mica, clay, thickener, a latex binder,talc, perlite, expanded perlite, or combinations thereof.
 5. The methodof making the joint compound of claim 1, wherein the wax emulsioncomprises: water; polyvinyl alcohol; paraffin wax, or montan wax, orsynthetic wax, or combinations thereof; a base; and a dispersant.
 6. Themethod of making the joint compound of claim 1, wherein the jointcompound comprises the wax at about 0.1% to about 8% of the jointcompound dry weight.
 7. The method of making the joint compound of claim1, wherein the joint compound has a pH below
 9. 8. The method of makingthe joint compound of claim 1, wherein the joint compound has a contactangle of about 90 to about 130 degrees.
 9. The method of making thejoint compound of claim 8, wherein the joint compound is hydrophobic andhas a contact angle of about 110 to about 130 degrees.
 10. The method ofmaking the joint compound of claim 1, wherein the joint compound has aCobb value of about 5.0 to about 200 grams per square meter.
 11. Themethod of making the joint compound of claim 10, wherein the jointcompound has a Cobb value of about 65 grams per square meter.
 12. Themethod of making the joint compound of claim 1, wherein the jointcompound further comprises surface micro-roughened fillers.
 13. Themethod of making the joint compound of claim 1, wherein the jointcompound comprises the wax at about 0.5% to about 4% of the jointcompound dry weight.
 14. The method of making the joint compound ofclaim 3, wherein the thickener comprises cellulose ether.
 15. The methodof making the joint compound of claim 5, wherein the base is monethanolamine, diethanol amine, triethanol amine, imidazole, or potassiumsiliconate.
 16. The method of making the joint compound of claim 5,wherein the dispersant is a lignosulfonate.